LOW LUNG CAPACITY AND HYPOXEMIA IN CHILDREN WITH THALASSEMIA MAJOR

Abstract

Lung function was evaluated in 17 children with thalassemia major in stable condition, receiving blood transfusions at regular intervals and s.c. deferoxamine daily. Total lung capacity (TLC) was below 2 SD of normal values for height in 7 of the 17 children and arterialized capillary PO2 [O2 partial pressure] was below the normal range in 15. Lung mechanics were studied in 4 children with reduced TLC. Static and dynamic compliance below 2 SD of normal values for height were found in 3, and lung recoil at TLC above normal values and specific upstream conductance (Gus/TLC) above 2 SD of normal values were found in all 4. Although these alterations in lung function occur in pulmonary fibrosis patients, no fibrosis was found in autopsy specimens of lung from 8 other patients with thalassemia. The rate constant of CO diffusion (kCO) was above the predicted mean in 14 of 15 children. Apparently there is a decrease in the growth of airspace relative to the vascular bed and major airways during childhood.